Here's my new Com-Bat; Test flights-Take 2

RknRusty wrote:I fell asleep listening to the Carolina baseball game. They won.
There's enough light now to fly after the pre-schoolers have gone, about 6:30PM. I have the flight box and stooge packed and ready to roll, so if I'm not too wiped out from dialysis I'll go tomorrow.
I replaced the G/N head with a regular Bee head to tone the Medallion down a bit. It was running 21k with 5 shims earlier. Seemed too much for the maiden of such a small untested plane.

Just saw the photos of your finished bat (good ole dial-up!)...what a flash back !!!! That little monster ought to leave a vapor trail !
I really hate to hear that you have to deal with dialysis Rusty !
Hope your day does go well and that you can test-fly it.

Good luck Rusty. I think it is going to fly just fine. That's a really nice install of the fuel bladder btw.

Dialysis is no party and one heck of a day changer. I dont have to do that but a family member does.

RknRusty wrote: I'm not too wiped out from dialysis I'll go tomorrow.

Rusty:

Take good care of yourself because you are appreciated around here and probably more than you realize.

Kind regards,

Thanks Dave, PV, I've been doing dialysis non-stop for 26 years, so I've got the hang of living with it. Restricting fluid intake, and knowing what's dangerous to eat too much of, all takes some time to learn and longer to develop discipline. But judging from some of the whining I hear from many healthy people, I think I feel about as good as they do... or better. You just have to show it who's boss and keep on living. I still have too many fun things left to do to let it kick my ass.

Your's is the best attidue Rusty and I admired you for it.

I've had a serious stroke which left me legally, but not totally, blind. In my therapy it was stressed to me to make the best of the life and vision that I have remaining not not dwell of the things I can no longer do.

Far and away the toughest problem that I face dialy is the fact that I can no longer drive a vehicle safety making me depend on others to get me about. The loss of independence is, at times, morbidly depressing but I am blessed with an excellent support network of family and friends.

My modeling keeps me sane through it all and the thought that there are others far worse off. I'm sure for find consolation n similar thoughts.

Hang in because there is much more life in us yet; it's meant to be lived and enjoyed to the fullest.

Well Rusty, you certainly have a good attitude about it, both you and Dave. Kudo's to both. One of the things Granny told me on her final bed was to live every day like it is your last few remaining, not your last remaining, but your last few,,And that life is to short. I try to have that attitude in everything I do, sometimes it is tough.

I've learned a lot of things like that. Here's a random Rustyism that I'm sure isn't an original thought: Pain - it's how you can tell you're still alive.

Okay, back to things we do for fun.
I took the Bat out today.

The setup was: the Medallion, which I dialed back from the mid 20k test run of Sunday, by changing to a stock Bee head; still had the APC 5.5x2 prop; the c/g was set to the most rearward and sensitive recommended point with fuel; the stabilator set to the minimum throw, but is still over 50° from horizontal, both up and down, an appalling amount which would tail stall most planes (35° is usually much too much); and last of all, a 5' crepe streamer.

Okay, here we go. I gave it a half tank of fuel and cranked the engine, ran it up and was needling it for takeoff when it sucked in the streamer with a WHOP! And it looked like a ticker tape parade had just marched by, covering me and my general area with red confetti. Well we won't have to worry about that happening again. So, I cranked it again and rolled it off just barely rich, picked up the handle and pulled it out of the stooge. I usually give a plane a slight bump of up to make sure and clear the ground, and it took off immediately into a loop and came back and landed on the stooge. Okay, note to self: no up elevator on launch. Next crank, I pulled it free and did an up-down wiggle and belly flopped in the grass. Next crank, I got it airborne fairly well for the first 10 feet, eased up and it went into a loop which I pulled out of. Somehow, I have no idea why, the lines were slack and it nosed in. Broke the prop. I heard my wife holler and looked up to see her sitting on the front porch of the house shouting, Well that wasn't much of an exhibition!. So I tossed it all in the wagon and pulled it home... fairly disappointed and fairly surprised. I have never, since I mastered C/L, had a plane I couldn't use a light enough touch on.

What I learned and other observations:
Most importantly, maybe, is the C/G needs to be moved up to the most forward, least twitchy, recommended position, meaning giving it a heavy steel necklace. That should retard its tendency to do a loop with the slightest touch of Up.

Next, of possibly equal importance is to make some stops to keep the elevator throw down to 35°, still too much for most planes. I'll have that ready, but wait until I first test it with the new C/G.

Prop it up to a backwards Cox 6x3. I think this plane is meant to have a relatively lethargic gray backed Bee pulling it. My SPI equipped Medallion runs as fast as some Tee Dees.

Put a rock from the driveway on top of the tip of the streamer so it won't get chopped off again.

Today had been long and I was hoping to reward myself with some fun high speed aerial antics, and also hoping to file a fine report here with y'all. Luckily there is not a scratch on the plane, other than a busted prop, so it'll keep. Rain is in the forecast, but I'll get back to it as soon as I can.

Our young friend Godsey built one of these last month and has been out flying wild until he wore out his hinges. He says he uses max throw on the elevator, which on mine would be close to 90°. He also said he made it massively nose heavy. I don't know where his C/G is but it must be in another dimension in front of the plane. He also describes the plane's ability to fly as "Awesome!" I can't remember what engine he's using. However I'm going to stick with the trimming methods that have always worked for me, and hopefully keep the weight reasonable. Godsey, maybe you'd like to weigh in on this, maybe I could use some advice.
Yes I did video it. No you may not see it.

This is Rusty's official report signing out.

I meant to add to my observations: there cannot possibly be another model engine of any type, at any level of performance, that is easier to crank and needle than the Cox Medallion .049. This is an awesome engine. I must get more. They were fairly tame in their original form with a #2 clunker of a cylinder that really needs a tracheotomy and an oxygen tank. But a G/N head and a new style SPI set, and 25% nitro, this thing ain't all that far behind a Tee Dee on pressurized 35%. Just more user friendly. And it'll draw fuel like a shopvac. And there is no reed to fiddle with, no backplate to leak, hardly any reason to test run one that's been sitting clean and oiled for any length of time. First time every time. Try that with any reedie, I dare you. No fuss no muss.

What is a G/N head?

microflitedude wrote:What is a G/N head?

A Galbreath head with a Nelson glow plug. Outperforms just about all other high compression heads, afaIk.

Rusty that is hilarious, especially to me since it brings back memories of a very similar incident that occurred back in the mid-50’s. It was my first flying wing, (it was called a WOW) powered with a Fox 35. Also my first experience with a seriously tail heavy plane. I told my buddy to just let it go level. Well he instinctively gave it a bit of up and I likewise held some up. So with zero airspeed it just sort of hung on the prop and flipped over on its back. There he was eye-ball to eye-ball looking at a plane barely an arm’s reach away coming straight at him. He managed to duck and then the fun began. The lines went slack so I ran back to try to get tension. Then it flew past me so I turned around and ran the other direction. When it hit the end of the lines the sudden jerk spun it back toward the center and the cycle repeated. That must have been the wildest exhibition of all time. I never had control but somehow managed to catch it with full up just before it powered in straight down. This went on for about half a tank. It finally wiped out with just a busted prop. Moved the engine forward and it was a great flyer.
Al

That's hilarious Big Al. Makes me feel better too. I'm not accustomed to walking off the field after being treated like that by a plane.

RknRusty wrote:I meant to add to my observations: there cannot possibly be another model engine of any type, at any level of performance, that is easier to crank and needle than the Cox Medallion .049. This is an awesome engine. I must get more. They were fairly tame in their original form with a #2 clunker of a cylinder that really needs a tracheotomy and an oxygen tank. But a G/N head and a new style SPI set, and 25% nitro, this thing ain't all that far behind a Tee Dee on pressurized 35%. Just more user friendly. And it'll draw fuel like a shopvac. And there is no reed to fiddle with, no backplate to leak, hardly any reason to test run one that's been sitting clean and oiled for any length of time. First time every time. Try that with any reedie, I dare you
. No fuss no muss.

Then you have never had a frog 100 or a mills :)first flick every time given a decent prime.
My Frog 100 doesn't require needling and will simply chug along at anywhere from 1.5 turns to around 6.

The 1st one I built was nose heavy. The second one was on the bellcrank. The throws do near the 90 degree mark. I flew mine with a Black Widow running 25% and a Yellow 5x3. The first one was fairly easy to fly. It was pretty soft. The second was ridiculous. I had to fly it about 10 times to keep it still. It was my first sporty plane.

RknRusty wrote:I've learned a lot of things like that. Here's a random Rustyism that I'm sure isn't an original thought: Pain - it's how you can tell you're still alive.

Okay, back to things we do for fun.
I took the Bat out today.

The setup was: the Medallion, which I dialed back from the mid 20k test run of Sunday, by changing to a stock Bee head; still had the APC 5.5x2 prop; the c/g was set to the most rearward and sensitive recommended point with fuel; the stabilator set to the minimum throw, but is still over 50° from horizontal, both up and down, an appalling amount which would tail stall most planes (35° is usually much too much); and last of all, a 5' crepe streamer.

Okay, here we go. I gave it a half tank of fuel and cranked the engine, ran it up and was needling it for takeoff when it sucked in the streamer with a WHOP! And it looked like a ticker tape parade had just marched by, covering me and my general area with red confetti. Well we won't have to worry about that happening again. So, I cranked it again and rolled it off just barely rich, picked up the handle and pulled it out of the stooge. I usually give a plane a slight bump of up to make sure and clear the ground, and it took off immediately into a loop and came back and landed on the stooge. Okay, note to self: no up elevator on launch. Next crank, I pulled it free and did an up-down wiggle and belly flopped in the grass. Next crank, I got it airborne fairly well for the first 10 feet, eased up and it went into a loop which I pulled out of. Somehow, I have no idea why, the lines were slack and it nosed in. Broke the prop. I heard my wife holler and looked up to see her sitting on the front porch of the house shouting, Well that wasn't much of an exhibition!. So I tossed it all in the wagon and pulled it home... fairly disappointed and fairly surprised. I have never, since I mastered C/L, had a plane I couldn't use a light enough touch on.

What I learned and other observations:
Most importantly, maybe, is the C/G needs to be moved up to the most forward, least twitchy, recommended position, meaning giving it a heavy steel necklace. That should retard its tendency to do a loop with the slightest touch of Up.

Next, of possibly equal importance is to make some stops to keep the elevator throw down to 35°, still too much for most planes. I'll have that ready, but wait until I first test it with the new C/G.

Prop it up to a backwards Cox 6x3. I think this plane is meant to have a relatively lethargic gray backed Bee pulling it. My SPI equipped Medallion runs as fast as some Tee Dees.

Put a rock from the driveway on top of the tip of the streamer so it won't get chopped off again.

Today had been long and I was hoping to reward myself with some fun high speed aerial antics, and also hoping to file a fine report here with y'all. Luckily there is not a scratch on the plane, other than a busted prop, so it'll keep. Rain is in the forecast, but I'll get back to it as soon as I can.

Our young friend Godsey built one of these last month and has been out flying wild until he wore out his hinges. He says he uses max throw on the elevator, which on mine would be close to 90°. He also said he made it massively nose heavy. I don't know where his C/G is but it must be in another dimension in front of the plane. He also describes the plane's ability to fly as "Awesome!" I can't remember what engine he's using. However I'm going to stick with the trimming methods that have always worked for me, and hopefully keep the weight reasonable. Godsey, maybe you'd like to weigh in on this, maybe I could use some advice.
Yes I did video it. No you may not see it.

This is Rusty's official report signing out.

Rusty, Great flight report for the Com-Bat !! The real C/L experienced guys on this forum will give you the best feedback but, my first thought, was that you are running a really tricked out Medallion in a very short coupled airframe. In other words, way too much power for such a short plane that would be hyper critical in where the cg is.
I had a tough health issue last year but nothing to compare with what you're going thru.Your attitude lets you overcome what most whiners couldn't take.
To quote our family Doctor who is my same age " Getting old is not for Sissies".....
Great work and God Speed....Steve

Thanks Malibu, your Doc was right about that. I visited 3 of them yesterday, man just going to see them is enough to make one feel ill.

Also, I just watched the video of yesterday's final launch. I was mistaken, I did have it leveled off a few feet off the ground and the engine quit before it turned down and hit the ground. Either it ran out of fuel or the prop broke(it had taken a pounding and I broke the safety rule of nicked props). It looks like like I might have had it that time. I'll trim it as I mentioned above and try it on the tall stooge this afternoon if the rain holds off.

Great stories, guys. Absolutely great stories --- always enjoy reading Rusty's flight reports.

I finished re-trimming it in time to fly, but it started drizzling. I added a hex nut and zip tie necklace to the engine. It's a lot of weight but the C/G is still about the same. Not much leverage there. And a black 6x3 Cox prop, backwards. If I can't fly that, I QUIT!. Just kidding. Now that I looked at the video of the last launch and see that it was level but still under flying speed, I feel like it would have flown, had the engine not quit(that's why the lines slacked). It all happened so fast, the video was the only way to see what happened. On every launch I had to recover from an ugly wobble. I'll bungee the stooge table to the bar stool next time to get a little more height.

The Stuntman is funny off the short stooge, it sometimes sinks and does a quick wheel hop on the sidewalk before jumping into the air. The Satan and Bean both behave well and fly right off from it. The Bean is out for the season.

I went looking for the prop blade today but couldn't find it.

Tomorrow.

andrew wrote:Great stories, guys. Absolutely great stories --- always enjoy reading Rusty's flight reports.

Thanks Andrew, I really enjoy writing and this has been a great and forgiving outlet. Even more so than RCG.

RknRusty wrote:

andrew wrote:Great stories, guys. Absolutely great stories --- always enjoy reading Rusty's flight reports.

Thanks Andrew, I really enjoy writing and this has been a great and forgiving outlet. Even more so than RCG.

Yes...I feel like I ought to check in on this too. I love the experiments and stories of same! If I can't settle in and really READ them, I make a note to get back when things are calm so they'll register.

I may have said this before...but this forum is the closest I've gotten to those "Good Ole Days" when I never knew WHAT my friends were gonna bring to the ballpark on Sunday afternoons !

Anybody wondering what happened with the Li'l Bat plane? Well, maybe not, but I played with it Saturday. Squirrelly little sucker. During our last episode we chewed the tail off and made confetti, launched into a backflip landing back on the stooge, launched into a tail dance ending 10 feet in front of the stooge, and finally recovered from the immediate post launch antics only to level off and have the prop bust. That's my theory as it cut off and then hit the ground and there was no prop blade anywhere to be found. Could have been buried in the ground.

Anyway, I figured I needed to move the c/g forward to stop the duck tail dance on every launch, so I gave it a larger hex nut necklace. The c/g wouldn't budge, as the Medallion is mounted right on the front of the wing and is so light weight. So our next episode begins with the added nose weight and a 6x2 prop instead of a 5.5x2. Cranked it up pulled it out of the stooge and it tail danced and wallowed around momentarily until I leveled off and by dangit, I was flying. I went a lap or two gradually increasing control input to make sure it wasn't going to take over control of itself. Soon I was doing climbs and dives and realized it was not capable of anything else. This wild weasel was flying like a PT19 with the down thrust set to Beginner.

After a bunch of laps I figured I should do something more. I could have turned it over and flown inverted. I could have probably done a figure 8. But I just uneventfully ran it out of gas and flopped it in with zero glide. It ain't gonna fly with all that nose weight and it ain't gonna fly without it. The only answer is that it's meant to have the heavy bulk of a tanked engine up front.

Enter the red headed Black Widow of the mouse racer rebuild thread. For our new members it can be found here: http://coxengineforum.forumakers.com/t1695-rebuilding-a-black-widow-mouse-racer-style?highlight=mouse+racer
It's been waiting to be called upon ever since the RR1 stole its job on the Li'l Satan. I put a new better aluminum pickup tube and a real metal BW backplate on it, and screwed it to the test block to see if it still ran. If I recall from the tach test video, it ran steady at 19,300 or so with a TF 5.25x4 prop.

I put a new Master Airscrew 5.5x3 prop on it and fueled it up. Gave it three flips to pump some fuel and hooked up the glow clip. 3.5 turns on the NV and no prime, gave it a rip and it started fast and riched out into a steady burble. I was startled, they never start without a prime. After a tankful to wet everything, I cut it loose and tached it at an unimpressive but steady 16,300 RPM. So then I tried some other props with much faster results. Here's what I got:
Master Airscrew 6x3 - 16,300
APC 5.5x2.5 - 18,300
APC 5.5x2 - 21,500 That's my baby! A 3,200RPM increase from a 2.5" to a 2" pitch prop.
APC 6x2 - 20,300... on a 6" prop. That's a first for me.

All steady runs, no wavering or needle chasing. It seems the pitch has more to do with easy spinning than I thought. It never ran over 21k with a 5" cox or a 5.25" TF propeller. Go figure. The mouse racer lives... until the Babe Bee crank lets go. I'll have a Killer Bee crank in a couple of weeks, but it already has a job. In a Killer Bee.

I have not yet mounted the Black Widow in place of the Medallion, but soon I will. When I do, I'll try the APC 6x2 first. I hope it will balance farther forward and end all that tail dancing and actually do what it's meant to do. It's delaying the start of my Flitestreak build. I'll keep you posted. And happily accept any ideas from the audience.

Hi rusty,

Always enjoy hearing of your adventures in modeling . If I were you I would chuck that piece of slab wood on the fire and get on with building the Streak. Any one that knows about planes and airfoils can tell you that a plank wing can fly but not well. Put the elevator on the wing went out of style over 50 years ago.Just a bad combo and a waste of time. The Baby Streak and Combat Kittens are better flyers than any thing that you have in your stable as of now.You need aircraft with good airfoils and moment arms.If it takes too long to build ,spring for a good 1/2A combat ARF. Just my 2 cents...

Mike 1484 (AMA)

I know, Mike, but my son gave me the Kom Bats for Christmas. Besides, when I finish playing with them I can set them up as anemic trainers so my sisters kids will have something to smash that won't hurt me. I'm about done but I cant let the little toy whip my ass.